Cutting knife



H. L. COHEN CUTTING KNIFE Jan. 14, 1941*.

Filed Feb. 24, 1940 1NVNT0R. BY HARRY LUS CHEN.

` @M L MU ATTORNEYS.`

Patented Jan. 14, 1941 i l n t y l UNITED STATES NPATENT ori-Ica CUTTING KNIFE Harry Louis Cohen, New York, N. Y., assigner to S. & S. Corrugated Paper Machinery Co., Inc.,

Brooklyn, N. Y., a corporation of New York Application February 24, 1940, serial Naseem 13 claims. (cl. 164-68) This invention relates to cutting knives and any demonstration or teaching of the use theremore particularly to synchronously operated of in connection with rotating knives, the speed knives adapted to cooperate with a continuous of rotation of which may be varied lwith respect web moving at a constant speed and arranged to the continuously moving web in order to obto cut sheets of predetermined length without tain cut olf sheets of different lengths (the speed 5 interfering with the continuous movement ofthe of the knife drum being varied so that it will be web and irrespective of thel average circumferexactly that of the continuously moving web durential speed of the knife. Y ing the cutting operation). The combination y For this latter purpose, this invention also reand usevof differential gearing arrangements in lates to the means for varying the circumferorder to achieve this purpose and the connec- 10 ential speed of rotating\knives during a cycle tion of the various members therethrough for thereof so that while the average circumferenthis purpose iS distinctly novel and advantatial speed may be different from the linear speed geous. Such use of the differential gearing arof a continuous web with which the knife corangement has at least one distinct advantage operates, the circumferential speed during the in that it involves the use of a member, the l period when the cutting operation takes place manufacture of which and the attributes of will be the'same as the linear speed of theweb. which are well known and understood.

Ordinarily where sheets of only one particular Consequently in the manufacture of this delength are to be cut from a continuously moving vice there will be no substantial unsolved probweb, the circumference and speed of rotation of lems with relation to the 4construction of the the knife drum may be so arranged that the differential itself. It is the placement of the circumferential speed of the knife blade will aldifferential mechanism in a particular position ways be equal to the linear speed of the continwith relation to the cutting knives and the speed uous web. The knife blade meets the web once changing mechanism which constitutes the induring each revolution, effecting the cutting opvention and not the differential mechanism by u eration as it passes along with the web at the itself. speed of the web, and then meeting the Web once Objects of this invention therefore are to promore at a distance from the original cut equal vide in a knife cutter a means for varying the to the length of sheet desired. speed of rotation of the knife drum cyclically The problems of adjustment of circumferenf during each revolution. Y

tial speed of the knife during a single revolu- Still another object of this invention is to protion thereof so that the knife will be moving at vide in a rotating knife cutting mechanism which the -speed of 'the paper during the actual cutis to be used to cut sheets of differing lengths ting operation and so that the average speed from a continuously moving web moving at' a I of rotation of the knife drum may be such as constant speed, means yfor varying the average 33 to give the predetermined sheet length which speed of rotation of the knife drums in order to will not necessarily be that produced by ordinary obtain sheets of different lengths and means for pure synchronous rotation of the knife drum varying the speed of rotation of the knife drums have been solved ihvarious different ways. once during each revolution so that during the 40 Thus, for instance, the shaft transmitting period in which the knife or knives are engaged (n power to the knife drum has not been connected with the continuously moving web, the knives directly to the knife drum itself but a device will be moving substantially at the speed of the producing an eccentric type of connection has web. Y been used in order that the effective radius of A` still further object of this present invention Lfyrotation of the power transmission shaftbe varied is to utilize a differential gearing arrangement once during a particular revolution of the knife for the purpose of obtaining a variation in the drum. This has been accomplished, for instance, speed of rotation of the knife drum once during by the crank and bifurcated arrangement shown each revolution. in Patent No. 2,208,350 or by the quadrc chair\\ Another object of this invention is to provide u arrangement shown therein or by other means differential gearing arrangement for eiecting such as that shown in application Ser. No. ghe result herein mentioned, the primary gear 318,294. 4 of said differential gearing arrangement being Although the differential gearing arrangement under the control of the mechanism which is commonly known and understood, nowhere in changes the average speed of rotation `ol. the the prior art or in theindustry has there been knife drums. 56

- connection with the following descriptionand drawing, in which:

Figure 1 is a schematic view in perspective showing the general operation of my machine.

Figure 2 is a cross-sectional view taken in plane 2-2 of Figure 1 looking in the direction of the arrows.

The continuously moving web I0 of corrugated board, brous or paper board or any other sheet material is fed at constant speed in the direction indicated by the arrow II` by the feed rollers I2 and I3. The feed rollers I2 and I3 are operated through the chain I4 and sprocket I5, the chain being Aoperated by the sprocket I6 attached to' and rotating with the shaft I1, the said shaft I1 being connected to the source of power.

The feed may be effected by the roll I2 alone pressing against the roll I3 or the feed rollers I2 and I3 may be interconnected by any suitable gearing arrangement in order to apply direct forward motive power tothe web IIJ lon both its upper and under surfaces. One of the cones I8 of a- Reeves drive I9 is fixedly mounted on the power shaft I1 and rotates therewith.

Belt 2U connects the cone I8 of the Reeves drive I9 to the cone 2l of the said Reeves drive, the cone 2I- being keyed to the shaft 22. The shaft 22 terminates at 23 in a disk 24 which is keyed to the shaft 22 and rotates therewith. The disk 24 carries a pin 25 non-.centrally mounted thereon. Link 26 is rotatably attached to -the pin 25 by means of the collar 21 so that rotation of the disk 24 and consequent rotation of the `pin 25 will cause the link 26 to oscillate in the manner and for the purpose hereinafter described,

It should be noted that any eccentric mounting of they pin 25`with' respect to the shaft 22 will serve the same purpose as the mounting thereof on the disk 24. 'Thus the pin 25 may be the terminal of a crank member mounted thereon or it may be eccentrically mounted with'f'f/respect to its shaft in any other suitable manner. Likewise the pin mounting'25 may, if desired, be an adjustable one, that is, it may be so mounted as to be slidable towards or away from the center of rotation ofthe shaft 22. For this purpose, the pin may be mounted in a slot of the disk or of t a crank keyed to the end of the shaft and releasably secured in any predetermined position on such slot as, for instance, by bolts or flanged Bevel gear 28 is keyed to the shaft 22 and rotating therewith meshes with bevel gear 29 so that the rotation of shaft 22 results in the rotation of shaft 30 which in turn through bevel gear 3l keyed to the oppposite end thereof rotates the primary gear 32 of the differential gearing arrangement 33 and thereby causes a rotation of the housing 34 of the differential gearing arrangement (see also Figure2).

As seen in Figure 2, the housing 34 of the differential gearing arrangement 33 has two bevel gears 35 and 36 rotatably mounted therein on pins 31 and 38 which are connected to and rotate withthe housing. Shaft 39 (Figures 1 and 2) extends through the bearing 40 into the housing 34 in such manner that the housing 34 may rotate about the shaft 39. Shaft 39 is keyed to bevel gear 4I which is enmeshed with bevel gears 35I and 36. Likewise shaft 42 extends. through the bearing 43 in the housing 34 in such manner that the housing may rotate with respect to the shaft 42. The shaft 42' is keyed to the bevel gear 44 which also is enmeshed on the opposite side with the bevel gears 35 and 36.

Assuming nowthat shaft 39 is held stationary so that bevel gear 4I is stationary then rotation of shaft 38 will through bevel gear 3I result in rotation of bevel gear 32 which in turn will result in rotation of the housing 34. The rotation of the housing 34 will carry the bevel gears 35 and 36 around with it, the bevel gears 35 and 36 being rotatably mounted also with respect to the housing and on an axis at right angles to the axis of rotation'thereof. Consequently if the .shaft 39 is held stationary so that the bevel gear 4I is held stationary, then rotation of the housing 34 will cause the bevel gears 35 and 36 to rotate about their own pins or axis 31 or 38 by reason of their continuous displacement with respect to the bevel gear 4 I.

However, if bevel gears 36 and 35 are thus .forced to rotate, they will, by reason of the fact that they are enmeshed with the bevel gear 44, cause the said bevel gear to rotate as well. The rotation of bevel gear 44 will result in rotation of the shaft 42 which in turn will result in rotation of the knife drum 45. rI'he shaft 42 drives shaft 46 through the gears 41 and 48 so that rotation o f shaft 42 will also result in rotation of knife drum 49 which is keyed to shaft 46. As hereinabove described, therefore, the rotation of the power shaft I1 will through the Reeves drive I9 cause a rotation of the shaft 22 which through bevel gears 28 and 29 will cause the rotation of the shaft 3U, which through the bevel gear 3| and the differential gearing arrangement 33 will result in rotation of the knife drums.

Movement of the belt 20 of the Reeves drive I9 in either direction will result in a speeding up or slowing down of the shaft 22 in a manner which is now well known in the art. Consequently movement of the belt 20 in 'either direction and by any suitable means will cause a variation in the speed of rotation of the knife drums 49 t and 45. Such variation in speed of rotation of the knife drums 49 and 45 is for the purpose of varying the length of each individual sheet cut from the moving web Ill. The reason that the speed of rotation of theknife drums is preferably varied for different lengths of cut-offs rather than the speed of linear movement of the web is that frequently the cutting operation is made as the web is led from the various manufacturing 'processes in which it was formed. Since the web is delivered from the filial step of such forming or manufacturing processes at a constant speed, which cannot readily be varied without changing many of the prior manufacturing processes, it becomes simpler to drive the web I0 directly from the power shaft I1, using any suitable gear ratio to maintain the desired speed at a constant unvarying level.

The Reeves drive I9 and the adjustment thereof may be used,.l1owever, to vary the speed While the cutting operation is relatively'fast,

nevertheless 4the action usually is a shearing action in which different points on the knife blades are progressively in engagement with the sheet so that the knives are in engagement with the sheet not merely at a particular instant of time but over an appreciable though relatively short period so that if the knife blades 50 and 5l mounted on the drums and 49 are not travelling at the speed of the sheet |0 during the cutting operation, tearing or deformation of the sheet I0 will occur.

It therefore becomesl beneficial to vary the speed of the knife drum during eachY revolution so that at the moment of cutting, the knife drum will be revolving so that the circumferential speed of the blades `and 5| will equal the linear speed of the paper while the speed of. the knife drums may be otherwisevaried during the balance of the rotation so that the average speed of rotation of the knife drums Will be that desired for the production of the sheet of selected length. For this reason, the shaft 39 which is keyed to the bevel gear 4| (Figures 1 and 2) is not'held in xed relation .(which was the position assumed for purposes of explanation hereinabove) but it is so arranged that it may be periodically rotated first in one direction and then in the other in order to vary the speed of the knife drum in accordance with the speed of the paper.

Shaft 39 carries at the opposite end from bevel gear 4| gear 52 which is keyed thereto and rotates therewith. Rack 53 vbears on gear wheel 52 and is enmeshed therewith Yso vthat a movement 51 to the link 26. It will be seen now that as the Y shaft 22 rotates, each rotation thereof by reason of the fact that bevel gears 28 and 29 are in one to one ratio result in a single rotation of the shaft 39. Likewise, each rotation thereof results in a single rotation of the disk 24 and consequently of the pin 25. Likewise, bevel gear 3| l and bevel gear 44 are inone to one ratio so that each rotation of shaft 22 results in a single rotation of the knife drum.

"Pin 25 rotates once for each revolution of the knife drum. When the pin 25 is in the position shown, it is, through the link 26, the pin 51, the adjustable mechanism 56, the rod 55 and couple 54, pulling the rack 53 in the direction shown by the arrow 58. Such movement of the rack 53 causes a rotation of the gear 52 resulting in a corresponding rotation of the shaft 39 which results in a corresponding rotation of the. bevel gear 4 I. l

The bevel gear 4| is thus rotated in a direction opposite to that in which the housing 34 is being rotated and consequently causes the bevel gears Y 35 and 36 attached to the housing to rotate more rapidly, consequently causing a faster rotation of the knife drums 49 and 45.

The distance of the pin 25 from the center of the shaft 22 is so adjusted that when the pin 25 is in the position 'shown in Figure 1, and the knife blades 50 and 5| are in engagement'as.

shown, the knife blades are caused to travel at the speed of the paper.

When the pin 25 has moved 90 further in its rotation, then the rack 53 will have momentarily icome to rest and consequent rotation of the shaft then the rack 53 will have been forced in the other direction resulting in the rotationof the shaft 39 and the bevel gear 4| in the opposite direction, thus resulting in a slowing down of the rotation of the shaft 42 and the knife drums. this slowing down being exactly equal to the amount by which the knife 42 and the drums have been speeded up so that the predetermined average speed will have been maintained in order to obtain sheets of the selected length while the knife drums will have been permitted to travel at the speed of the moving web during the moment of cutting. As previously pointed out, the pin 25 lmay be made adjustable with respect to the center of rotation of the shaft 22 in order to obtain finer variations in the speed changes. The adjustable mechanism 56 may also be used. The adjustable mechanism 56 comprises a'housing 59 pivotally mounted at 60 and freely rotatable thereat.4 The housing 59 carries the screw 6| rotatably mounted therein but not axially movable with respect thereto. Rotation of handle 62 will cause a rot-ation of the screw 6|. in threaded engagement with the screw .6| so that rotation of the screw 6| by the handle 62 will cause the nut 63 to travel along the screw 6|, particularly since the bolt 63 is prevented from rotation with respect to the housing 59 by reason of the fact that it rides in the groove 64.

The rod 55 is -pivotally connected to the nut 63 by the pin 65. It will now be seen that rotation of the pin 25 will result in oscillatory movement of the link 26 which through the pivoted mounting 51 will result in an oscillatory pendulum like motion of the housing 59 around the rotatable mounting 60 as a fulcrum. Such oscillatory motion of the housing 59 will result in a corresponding oscillatory motion of the nut 63 which in turn will result in oscillatory motion of the rod 55 and rack 53 for the purpose of causing the shaft 39 and the bevel gear 4| to rotate rst in one direction and then in the Aopposite direction for the reasons hereinabove described.

It should benoted that disk 25 and pin 25 (virtually constituting a-single crank member), link 26, housing 59 and rod 55 virtually constitute a quadric chain, variation in the adjustment' of one of the elements of which will result in a variation in the motion transmitted from the first element tothe last element of the quadric chain.

Thus, adjustment of the position of the nut l63 on the bolt 6| and within the housing 59 by means of the handle 62 willI result in a variation of the relative 'speed of movement of the *rack 53 in order to adjust the speed of rotation of the knife drums so that during the cutting. period it will be,equal to that of the linearly moving web I0.

It should be noted that, in the figures, the type of adjustment shown is that for cutting sheets equal in length to the circumferential length of the knife drums or of the greater length. That is, when the nut 63 is adjusted so that the pin 65 is axially aligned with the rotatable mounting 60, then no cyclic variation of speed of rotation of the knife drums will occur, and ,the machine is set to cut sheets, of a length equal to the circumferential length of the knife drums. Virtually the same resultis obtained 'by making the mounting of the pin 25 adjustable; the knives then being arranged to cut sheets of a length equal to the circumference of the knife mountings when the pin 25 is adjusted to be axially aligned with shaft 22.

If the machine is to be arranged to cut sheets of lesser length than the effective circumferential length of the knife drums, then the housing 59 and screw 6I should be arranged to extend beyond and above the rotatable mounting 60; so that the nut 63 may be adjusted beyond said rotatable mounting 60 by a distance suicient to obtain the desired length of the sheet. Or, in the alternative, the pin 25, if adjustable, should be arranged to be adjusted beyond the shaft 22. In each case, the effect would be to reverse the oscillation of the housing 59 and obtain a slowing down of the knife drum where it would otherwise be speeded up `and vice versa. This, in effect, would be the same result asl if the positions of the knives in Figure 1` were shifted 180 while' be adjusted to cut sheets of any length, whether greater than their circumferential length or less. The operation of my machine -has been set forth in connection with the foregoing description, the operation of e'ach of the elements having been described in connectionl with the structure thereof. In general, it may be said that the speed of revolution of the knife drums for the purpose of varying the size of the sheet to be cut may be varied by adjustments of the Reeves drive. 'Ihis relates only to the average speed, however. There is superimposed upon this average speed, a cyclical vari-ation which results from the oscillatory motion induced from pin 25 into the rack 53 which causes variations through the differential gearing arrangement in the manner hereinabove described of the speed of rotation of the shaft 42 which controls the knife drums.

Where the knife drums are through the Reeves drive adjusted to rotate at a speed different from that of the linear movement of the web, then the handle 62 may be rotated to a position in which the movement of the rack 531 during the moment of cutting is such that the .speed induced in the knife drums at that moment is equal to that of the web, the'average speed of p rotation of. the knife drums being maintained by a corresponding slowing down or speeding up of the knife drums when the knife blades have travelled through 180.

It will be obvious of course that this device may have many uses in the cutting of constantly moving sheet material. It will also be clear that an integral adjustment may be arranged for the belt 20 of the Reeves drive I9 and the handle 62 so that movement of one will result in -a corresponding rotation or movement of the other to integrate the movement of the rack 53 with they speed of rotation ofthe 'knife drums, in such a manner that variation in one will induce corresponding variations in the other in order to preyvent disruption of the sheet during cutting operations.

In the foregoing description, I have set forth my invention by illustrations which are to be regardegl merely by Wayof example. Obviously this invention may be practiced in many different ways and may have many uses not herein specifically set forth which will be .clear to those skilled in the art. I therefore prefer to be limited not by the description herein, but only by the appended claims..

I claim':

1. A mechanism for cutting constantly moving sheet material into successive strips of predetermined length comprising a knife mounted on a rotatable shaft and cyclically engageable with said sheet; a differential gear mechanism; a source of power connected to and rotating the housing of said differential gear mechanism, said shaft terminating in a first gear forming part of the differential gear mechanism; a second gear within the differential gear mechanism; ro-

tation of the housing causing rotation of saidshaft; and means for rotating said second gear first in one direction and then in the opposite direction during each revolution of said lknife shaft to cause cyclic variation in speed thereof.

2. A mechanism for cutting constantly moving sheet material into successive strips of predetermined length comprising a knife mounted on a rotatable shaft and cyclically engageable with said sheet; a differential gear mechanism; a source of power connected to and rotating the housing of said differential gear mechanism, said shaft terminating in a first gear forming part of the differential gear mechanism; a second gear Within the differential gear mechanism, said gears being rotatably mounted with respect to the housing and with respect to each other, and being each engaged with idler gears mounted on shafts attached to the housing; rotation of the housing causing rotation of said shaft; and means for rotating said second gear first in one direction and then in the opposite direction during each revolution of said knife shaft to cause cyclic variation in speed thereof.

3. A mechanism for cutting constantly moving sheet material into successive strips of predetermined length comprising a knife mounted on a rotatable shaft and cyclically engageable with said sheet; a differential gear mechanism; a source of power connectedto and rotating the housing of said differential gear mechanism, said shaft terminating in a first gear forming part of the differential gear mechanism; a second gear within the differential gear mechanism; said gears being rotatably mounted with respect to the housing and with respect to each other, and being each engaged with idler gears mounted on shafts attached to the housing, rotation of the housing resulting in rotation of the shafts of said idlers in a plane normal to their diameters; means for controlling the rotation of said second gear thereby causing said housing and idlers to rotate said first gear, said means including members for rotating said second gear first in one direction and then in the other op- 76 posite direction during each revolution of said knife shaft to cause cyclic variation in speed thereof.

4. A mechanism for cutting constantly mov-V ing sheet material into successive strips of predetermined length comprising a knife mounted on a rotatable shaft and cyclically engageable with said sheet; a differential gear mechanism; a

source of power connected to and rotating the housing of said dierential gear mechanism, said shaft terminating in a first gearforming part of the differential gear mechanism; a second gear within the differential gear mechanism; rotation of the housing causing rotation of said shaft; and means for rotating said second gear first in one direction and then in the opposite direction during each revolution of said knife shaft to cause cyclic variation in speed thereof, said means comprising a shaft, said second gear being mounted' at one end of said shaft; a third gear mounted on said shaft; a rack engaging said third gear; said rack oscillating and completing one period of oscillation during, eachrevolution of the knife shaft.

5. A mechanism for cutting constantly moving sheet material into successive'strips of predetermined length comprising a knife mounted on a rotatable shaft and cyclically engageable with said sheet; a differential gear mechanism; a source of power connected to and rotating the housing of said differential gear mechanism, said shaft terminating in a firstA gear forming part of the differential gear mechanism; a second gear within the differential gear mechanism; said gears being rotatably mounted with respect toV the housing and with respect to each other, and being each engaged with idler gears mounted on shafts attached to the housing, rotation of the housing resulting in rotation of the shafts 4o of said idlers in a plane normal to their diameters; means for controlling the rotation of said second gear thereby causing-said housing and idlers to rotate said first gear, said means includ- .ing members for rotating said second gear first in one direction and then in the opposite direction during each revolution of said knife shaft to cause cyclic variation in speed thereof,.said means comprising a shaft, said second gear being mounted at one kend of said shaft; a third gear mounted on said shaft; a rack engaging said third gear; said rack oscillating and completing one period of oscillation during each revolution of the knife shaft.

6. A mechanism for cutting constantly moving 55 sheet material into successive strips of predemeans for rotating said second gear rst in one direction and then in the opposite direction during each revolution of said knife shaft to cause cyclic variation in speed thereof; said means comprising a shaft, said second gear be- 70 ing mounted at one end of said shaft; a third gear mounted on said shaft; and a rack engaging said third gear; said rack being coupled to an oscillating member, said oscillating member completing one period of oscillation during each 75 revolution of the knife shaft.

.of said knife shaft and completing one period 7. A mechanism for cutting constantly moving sheet material into successive strips of predetermined length comprising a knife mounted on a rotatable shaft and cyclically engageable with said sheet; a.r differential gear mechanism; a source of power connected to and rotating the housing of said differential gear mechanism; said shaft terminating in a rst gear forming part of the differential gear mechanism; a second gear within the differential gear mechanism; ro-

Itation of the housing causing rotation of said shaft; means for rotatingsaid second gear rst in one direction and then in the opposite direction during each revolution of said knife shaft to cause cyclic variation in` speed thereof; said means comprising a shaft, said second gear being mounted at one end of said shaft; a third gear mounted on said shaft; and a rack engaging said third gear; said rack being coupled to an oscillating member, said oscillating member comprising a shaft, and a housing pivotally mounted thereon, said coupling to said rack being adjustable with respect to said shaft, said oscillating member completing one period of oscillation during each revolution of the knifeshaft, f

8. A mechanism for cutting constantly moving sheet material into successive strips of predetermined length comprising a knife mounted on a' rotatable shaft` and cyclically engageable with said sheet; a differential gear mechanism; a source of power connected to and rotating the housing of said differential gear mechanism; said shaft terminating in a first gear forming part of the differential gear mechanism; a second gear within the differential gear mechanism; rotation ofthe housing causing rotation of said shaft; means for rotating said second gear first in one direction and then in the opposite direction during each revolution of said knife shaft to cause cyclic variation in speed thereof; said means comprising a shaft, said second gear being mounted at one end of said shaft; a third gear mounted on said shaft; and a rack engaging said third gear; said rack being coupled to an oscillating member, said oscillating member comprising a shaft, and a housing pivotally mounted thereon, said coupling to said rack being adjustable with respect to said shaft, said oscillating member being connected by a link to the source of power of oscillation during each revolution of the knife shaft. A

9. A mechanism for cutting constantly moving sheet material into successive strips of predetermined length comprisingla knife mounted on a rotatable shaft and cyclically engageable with said sheet; a differential gear mechanism; a source of power connected to and rotating the housing of said differential gear mechanism; said shaft terminating in a first gear forming part of. the differential gear mechanism; a second gear within the diiferential gear mechanism; rotation of the housing causing rotation of said shaft; means for rotating said second gear first in one direction and then in the opposite direction during each revolution of said knife shaft to cause cyclic variation in speed thereof; said means comprising a shaft, said second gear being mounted at one end of said shaft; a third gear mounted 70 on said shaft; and a rack engaging said third gear; said rack being coupled to an oscillating member, said oscillating member comprising a shaft, and a housing pivotally mounted thereon,

` said coupling to said rack being adjustable with respect to said shaft, said oscillating member being connected by a link tothe source of power of said knife shaft and completing one period of oscillation during each revolution of the knife shaft; said source of power comprising a shaft rotatingat the speed of said knife shaft, said latter shaft carrying a member rotating about the center thereof, said link being connected thereto.

10.4 A mechanism for cutting constantly moving sheet material into successive strips of predetermined length comprising a knife mounted on a rotatable shaft and cyclically engageable with said sheet; a differential gear `mechanism; a

source of power connected to and rotating theV p prising a shaft, said second gear being mounted at one end of said shaft; a third gear mounted on said shaft; and a rack engaging said third gear; said rack being coupled to an oscillating member, said oscillating member comprising a shaft, and a housing pivotally mounted thereon,

said coupling to said rack being adjustable with respect to said shaft, said oscillating member being connected by a link to the source of power of said knife shaft and completing one period of oscillation during each 'revolution of the knife shaft; said source of power comprising a shaft rotating at the speed of said knife shaft, said latter shaft carrying a member rotating about the center thereof, said link being connected thereto, said last mentioned member being adjustable with respect to its distance from the center of rotation of said latter shaft.

11. A mechanism for cutting constantly moving sheet material into successive strips of predetermined length comprising af knife mounted on a rotatable shaft and cyclically engageable with said sheet; a speed changing mechanism; a

Asource of power connected to and driving said shaft through said speed changing mechanism; and means for varying one setting of saidspeed changing mechanism during each cycle of said knife; said means comprising an oscillating member and a connection between said oscillating member and said speed changing mechanism; movement of said connection effecting adjustment of the speed changing mechanism; said oscillating member comprising a shaft and a housing pivotally mounted thereon; said connection between said oscillating member and said speed changing mechanism being adjustable with respect to the shaft; said oscillating member being connected by a link to the source of power of said knife shaft and completing one period of oscillation during each revolution of the knife shaft; said source of power comprising a shaft rotating at the speed of said knife shaft, said latter shaft carrying a member rotating about the center thereof, said link being connected thereto.

12. A mechanism for cutting constantly moving sheet material into successive strips of predetermined length comprising a knifemounted on a' rotatable shaft and cyclically engageable with said sheet; a speed changing mechanism; a source of power connected to and driving said shaft through. said speed changing mechanism; and means for varying one setting of said speed changing mechanism during each cycle of said knife; said means comprising an oscillating member and a connection between said oscillating member and said speed changing mechanism;

movement of said connection effecting adjust-` ment of the speed changing mechanism; said oscillating member comprising a shaft and a housing pivotally mounted thereon; said connection between said oscillating member and said speed changing mechanism being adjustable with respect to the shaft; an adjustment member carried by said housing, said connection between said oscillating member and said speed changing mechanism being connected to said adjustment member, operation of said adjustment member changing the position of said connection with respect to the oscillating member shaft; said oscillating member being connected by a link to the source of power of said knife shaft and completing one period of oscillation during each revolution of the knife shaft; said source of power comprising a shaft rotating at the speed of said knife shaft, said latter shaft carrying a member rotating about the center thereof, said `link being connected thereto.

13. A mechanism for cutting constantly moving sheet material into successive strips of predetermined length comprising a knife mounted on a rotatable shaft and cyclically engageable with said sheet; a speed changing mechanism; a source of power connected to and driving said shaft through said speed changing mechanism; and means for varying one setting of said speed changing mechanism during each cycle of said knife; said means comprising an oscillating member and a connection between said oscillating member and said speed changing mechanism; movement of said connection effecting adjustment of ,the speed changing mechanism; said oscillating member comprising a shaft and a housing pivotally mountv of said knife shaft and completing one period` of oscillation during each revolution of the knife shaft; said source of power comprising a shaft rotating at the speed of said knife shaft, said latter shaft carrying a member rotating about the center thereof,V said link being connected thereto.

HARRY LOUIS COHEN. 

